Effects of an Eccentric Hamstrings Training on Components of Physical Performance in Young Female Handball Players

Effects of a horizontal speed deceleration training programme on measures of physical fitness in youth male handball players

This study examined the effects of an 8-week horizontal speed deceleration training (HSDT) programme in combination with regular handball-specific training as compared with handball-specific training only in measures of physical fitness in male youth handball players. Thirty-nine players were randomly assigned to either an HSDT group (n = 18; 15.55 ± 0.24 years) or an active-control group (CG; n = 21; 14.59 ± 0.23 years). The results showed significant and large between-group differences at post-test in countermovement jump, change-of-direction speed, and repeated sprint ability (RSA) (all p < 0.01; d = 2.04 and 1.37, 1.39, 1.53, and 1.53 for the CMJ, 505 CoD, RSAbest, RSAaverage, and RSAtotal performances, respectively). The post-hoc-analysis demonstrated significant and large improvements in all measures of physical fitness in the HSDT group (∆2.49% to 16,25%; d = 1.01 to 1,70; all p < 0,01). The CG, however, failed to reach any significant difference in all measures of physical fitness ((∆0.31% to 1.98%; d = 0.15 to 0.22; p = 0.379; p > 0.05). To summarise, an 8-week in-season HSDT programme alongside regular handball-specific training yielded positive effects on various performance measures including jumping ability, CoD speed, and RSA, when compared to handball-specific training alone. These results highlight the potential benefits of integrating HSDT into the training regimen of youth handball athletes during the competitive season.

Linear and Change of Direction Repeated Sprint Ability Tests: A Systematic Review

ABSTRACT

Kyles, A, Oliver, JL, Cahill, MJ, Lloyd, RS, and Pedley, J. Linear and change of direction repeated sprint ability tests: a systematic review. J Strength Cond Res 37(8): 1703-1717, 2023-The ability to repeatedly sprint is important in many sports, but there is no established protocol for measuring repeated sprint ability (RSA). The purpose of this review was to identify overground RSA protocols previously reported in the literature and to recommend standardized protocols. A systematic review of the literature was used to identify studies that have used an RSA test, with data describing protocol design extracted. One hundred eight studies were included in the review, across which 47 unique protocols were identified. Eighteen protocols included at least one change of direction (COD), and this increased mean sprint time compared with linear RSA tests (7.26 ± 1.84 vs. 4.48 ± 1.02 seconds). There was considerable variability across protocols regarding sprint distance (20-40 m), sprint repetitions (3-15), recovery duration (10-60 seconds), recovery type (active vs. passive), and work-to-rest ratio (≤1:1.4-19.2). Separate protocols are needed for linear and COD tests, and these should reflect the brief nature of intense periods of competition and stress the ability to recover. Based on data across studies for protocol design and to ensure a demanding work-to-rest ratio, it is suggested that a linear RSA should comprise 6 × 30 m sprints separated by 15 seconds of active recovery. To provide some parity to linear tests, to keep work duration brief and to maintain a demanding work-to-rest ratio, a COD RSA should comprise 6 × 30 m shuttle sprints (15 + 15 m), providing one change of direction (180° COD), and maintaining a 15-second active recovery.

A Systematic Review of Flywheel Training Effectiveness and Application on Sport Specific Performances

The objective of this systematic review was to examine the effectiveness of flywheel training, which allows for the replication of specific sports movements, overloading both the concentric and eccentric phases. Inclusion criteria were injury prevention outcomes; ability in terms of strength, power, sprinting, jumping and change of direction; competitive athletes; and RCTs. Exclusion criteria were a lack of a control group and lack of baseline and/or follow-up data. The databases used were Web of Science, Scopus, PubMed, Cochrane Library, and Sage. The revised Cochrane risk-of-bias tool was used to assess the quality of the selected RCTs. The Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence was used. A PICOS (participants, intervention, comparators, study outcomes, and study design) approach was used to evaluate eligibility. A total of 21 RCTs with 8 to 54 participants in each study analyzed flywheel technology and its application in nine sports. The results showed that flywheel training is a good strategy to improve sports performance, providing variation in training methodologies and athletes’ adherence. Further studies are needed to define guidelines on training modality, weekly frequency, volume, and inertia load. Only a few studies have applied the flywheel device directly to overload specific multidirectional movements at different joint angles. This method is not exempt from criticalities, such as the cost and the ability to carry out only individual training.

The effect of volume equated 1- versus 2-day formats of Nordic hamstring exercise training on fitness in youth soccer players: A randomised controlled trial

PURPOSE

This randomised controlled trial examined the effect of an 8-week volume-equated programme of Nordic hamstring exercise (NHE) training, executed at frequencies of 1- or 2-days per week, on fitness (10 m and 40 m sprint, '505' change of direction [COD] and standing long jump [SLJ]) in male youth soccer players (mean age: 16.4 ± 0.81 years).

METHOD

Players were divided into an experimental group (n = 16) which was further subdivided into 1-day (n = 8) and 2-day (n = 8) per week training groups and a control group (n = 8).

RESULTS

There were significant group-by-time interactions for 10-m sprint (p<0.001, η2 = 0.120, d = 2.05 [0.57 to 3.53]), 40-m sprint (p = 0.001, η2 = 0.041, d = 1.09 [-0.23 to 2.4]) and COD (p = 0.002, η2 = 0.063, d = 1.25 [-0.09 to 2.59). The experimental group demonstrated a 'very large' effect size (d = 3.02 [1.5 to 4.54]) in 10-m sprint, and 'large' effect sizes in 40-m sprint (d = 1.94 [0.98 to 2.90]) and COD (d = 1.84 [0.85 to 2.83). The control group showed no significant changes. There were no significant differences between the 1-day and 2-day training groups. In three of the four tests (40 m, COD, SLJ) the 2-day group demonstrated larger effect sizes. Ratings of perceived exertion (RPE) were significantly lower in the 2-day group (p<0.001, 3.46 [1.83 to 5.04).

CONCLUSION

The NHE increases fitness in youth soccer players and there may be advantages to spreading training over two days instead of one.

A randomised controlled trial of 1- versus 2-day per week formats of Nordic hamstring training on explosive athletic tasks in prepubertal soccer players

This randomised controlled trial examined the effect of volume-equated programmes of Nordic hamstring exercise (NHE) training, executed at frequencies of 1- or 2-days per week, on explosive athletic tasks (30 m sprint, 15 m manoeuvrability and standing long jump [SLJ]) in male youth soccer players (mean age: 10.3 ± 0.5 years). Players were divided into an experimental group (n = 31) which was further subdivided into 1-day (n = 16) and 2-days (n = 15) per week training conditions, and a control group (n = 14). There were significant group-by-time interactions for 30-m sprint (p < 0.001, d = 0.6), SLJ (p = 0.001, d = 1.27) and 15 m manoeuvrability (p < 0.001, d = 0.61). The experimental group demonstrated small to moderate effect sizes in 30-m sprint (d = 0.42, p = 0.077), SLJ (d = 0.97, p < 0.001) and 15 m manoeuvrability (d = 0.61, p < 0.001). The control group showed small significant performance decrements or no change in these variables. There were no significant differences between the 1-day and 2-day training groups. In two of the three tests (30 m sprint, SLJ) the 2-day group demonstrated larger effect sizes. The NHE enhances explosive athletic task performance in prepubertal youth soccer players and there may be only small advantages to spreading training over two days instead of one.

Quo Vadis Nordic Hamstring Exercise-Related Research?-A Scoping Review Revealing the Need for Improved Methodology and Reporting

The objective of this scoping review is to assess Nordic Hamstring Exercise quality (ANHEQ) of assessments and interventions according to the ANHEQ rating scales and to present practical recommendations for the expedient design and reporting of future studies. A total of 71 Nordic Hamstring Exercise (NHE) assessments and 83 NHE interventions were selected from the data sources PubMed, Scopus, and SPORTDiscus. Research studies which were presented in peer-reviewed academic journals and implemented the NHE during laboratory-based assessments or multi-week interventions met the eligibility criteria. NHE assessments analyzed force (51%), muscle activation (41%), knee angle kinematics (38%), and bilateral symmetry (37%). NHE interventions lasted 4-8 weeks (56%) and implied an exercise volume of two sessions per week (66%) with two sets per session (41%) and ≥8 repetitions per set (39%). The total ANHEQ scores of the included NHE assessments and interventions were 5.0 ± 2.0 and 2.0 ± 2.0 (median ± interquartile range), respectively. The largest deficits became apparent for consequences of impaired technique (87% 0-point-scores for assessments) and kneeling height (94% 0-point-scores for interventions). The 0-point-scores were generally higher for interventions compared to assessments for rigid fixation (87% vs. 34%), knee position (83% vs. 48%), kneeling height (94% vs. 63%), and separate familiarization (75% vs. 61%). The single ANHEQ criteria, which received the highest score most frequently, were rigid fixation (66% of assessments) and compliance (33% of interventions). The quality of NHE assessments and interventions was generally 'below average' or rather 'poor'. Both NHE assessments and interventions suffered from imprecise reporting or lacking information regarding NHE execution modalities and subsequent analyses. Based on the findings, this scoping review aggregates practical guidelines how to improve the design and reporting of future NHE-related research.

Effects of High and Low Training Volume with the Nordic Hamstring Exercise on Hamstring Strength, Jump Height, and Sprint Performance in Female Football Players: A Randomised Trial

The evidence-based hamstring strengthening programme for prevention of hamstring injuries is not adopted by football teams because of its high training volume. This study on female football players investigated if high-volume training with the Nordic hamstring exercise is more effective on hamstring strength, jump height, and sprint performance than low-volume training. We also examined the time course of changes in muscle strength during the intervention period. Forty-five female football players were randomised to a high- (21 sessions, 538 total reps) or low-volume group (10 sessions, 144 total reps) and performed an 8-week training intervention with the Nordic hamstring exercise during the preseason. We tested hamstring strength (maximal eccentric force with NordBord and maximal eccentric torque with isokinetic dynamometer), jump height, and 40 m sprint before and after the intervention. The NordBord test was also performed during training weeks 4 and 6. Both groups increased maximal eccentric force (high-volume: 29 N (10%), 95% CI: 19-38 N, p < 0.001, low-volume: 37 N (13%), 95% CI: 18-55 N, p = 0.001), but there were no between-group differences (p = 0.38). Maximal eccentric torque, jump height, and sprint performance did not change. Maximal eccentric force increased from the pretest to week 6 (20 N (7%), 95% CI: 8 to 31 N, p < 0.001), but not week 4 (8 N (3%), 95% CI: -2 to 18 N, p = 0.22). High training volume with the Nordic hamstrings exercise did not lead to greater adaptations in strength, jump height, or speed than a low-volume programme. Players in both groups had to train for at least 6 weeks to improve maximal eccentric force significantly.

The Influence of Maturity Status on Dynamic Balance Following 6 Weeks of Eccentric Hamstring Training in Youth Male Handball Players

Information about when to apply an appropriate eccentric hamstring strength training stimulus during long-term athlete development is essential for effective programming and improving balance performance. This study examined the effects of six-week eccentric hamstring training on dynamic balance performance in youth handball players of different maturity statuses (pre- or post-peak height velocity (PHV)). A randomized controlled design with 45 young male handball players (14.6 ± 0.3 years) from a local national handball club were randomly allocated to a 6 week, twice weekly eccentric hamstring training in two experimental groups: a pre-PHV (maturation offset: −2.13 ± 0.63, n = 10) and post-PHV (maturation offset: 0.79 ± 0.34, n = 12) group and two control groups: maturation offset: −2.09 ± 0.61, n = 10 and maturation offset: 0.55 ± 0.67, n = 13. Dynamic balance performance was evaluated by using the composite score during the lower quarter Y-balance test from pre- and post-intervention. A significant effect on balance scores was found from pre to post (F = 11.4; p = 0.002; η2p = 0.22), intervention (F = 5.4; p = 0.025; η2p = 0.12), and maturation (F = 369; p < 0.001; η2p = 0.9), but no significant interaction effects were found (F ≥ 3.3; p ≥ 0.077; η2p ≤ 0.07). Post hoc analysis revealed that the post-PHV group had a higher score than the pre-PHV group. Furthermore, that dynamic balance increased in the post-PHV group after intervention much more in the control post-PHV group. It was concluded that somatic maturation influences dynamic balance performance and that eccentric hamstring training results in greater improvement in balance performance in young male handball players for the post-pubertal group.

Effect of Flywheel versus Traditional Resistance Training on Change of Direction Performance in Male Athletes: A Systematic Review with Meta-Analysis

Objective: This study aimed to systematically review and meta-analyze the effect of flywheel resistance training (FRT) versus traditional resistance training (TRT) on change of direction (CoD) performance in male athletes. Methods: Five databases were screened up to December 2021. Results: Seven studies were included. The results indicated a significantly larger effect of FRT compared with TRT (standardized mean difference [SMD] = 0.64). A within-group comparison indicated a significant large effect of FRT on CoD performance (SMD = 1.63). For TRT, a significant moderate effect was observed (SMD = 0.62). FRT of ≤2 sessions/week resulted in a significant large effect (SMD = 1.33), whereas no significant effect was noted for >2 sessions/week. Additionally, a significant large effect of ≤12 FRT sessions (SMD = 1.83) was observed, with no effect of >12 sessions. Regarding TRT, no significant effects of any of the training factors were detected (p > 0.05). Conclusions: FRT appears to be more effective than TRT in improving CoD performance in male athletes. Independently computed single training factor analyses for FRT indicated that ≤2 sessions/week resulted in a larger effect on CoD performance than >2 sessions/week. Additionally, a total of ≤12 FRT sessions induced a larger effect than >12 training sessions. Practitioners in sports, in which accelerative and decelerative actions occur in quick succession to change direction, should regularly implement FRT.

Speed Improves With Eccentric Hamstring Training in Athletes of Different Maturity Status

PURPOSE

To investigate the effects of an eccentric hamstring strength training program (EHT) on sprint performance (10-, 20-, and 30-m sprint times) and change of direction speed (4 × 5-m shuttle run and T-Half test) in male European handball athletes at 2 maturity statuses (prepeak and postpeak height velocity [PHV]).

METHODS

Forty-five participants (12.68 [1.58] y) were divided into pre-PHV and post-PHV and randomly allocated to a control or intervention group, which performed a guided 2 day per week 6-week EHT of 5 exercises. A mixed-model (within- and between-factor) analysis of variance was conducted.

RESULTS

A significant effect (P < .05) of the interaction time × maturity × training was observed in the T-Half, 10, and 30 m tests. Both intervention groups significantly improved in all the tests, except in the 20 m sprint and the post-PHV in the 10 m sprint. Improvements ranged between 0.93% and 5.74% (effect size: 0.07-0.79). Both control groups yielded no improvements in almost all the tests. The improvements of both groups undergoing the intervention (pre-PHV and post-PHV) were not significantly different (only a tendency in the 10 m sprint).

CONCLUSION

An EHT program combined with European-handball training improve change of direction and sprint performance in pre-PHV and post-PHV male players. Professionals training European handball and similar team-sport athletes should consider including EHT regardless of athlete's maturity.

Isotonic and Isometric Exercise Interventions Improve the Hamstring Muscles’ Strength and Flexibility: A Narrative Review

Background: Hamstring weakness has been associated with an increased risk of hamstring strain, a common sports injury that occurs when athletes perform actions such as quick sprints. The hamstring complex comprises three distinct muscles: the long and short heads of the bicep femoris, the semimembranosus, and the semitendinosus. Methods: The researchers collected the data from different electronic databases: PubMed, Google Scholar, and the Web of Science. Results: Many studies have been conducted on the numerous benefits of hamstring strength, in terms of athletic performance and injury prevention. Isotonic and isometric exercises are commonly used to improve hamstring strength, with each exercise type having a unique effect on the hamstring muscles. Isotonic exercise improves the muscles’ strength, increasing their ability to resist any force, while isometric training increases strength and the muscles’ ability to produce power by changing the muscle length. Conclusions: These exercises, when performed at low intensity, but with high repetition, can be used by the healthy general population to prepare for training and daily exercise. This can improve hamstring muscle strength and flexibility, leading to enhanced performance and reduced injury risk.

Maximal isokinetic elbow and knee flexor-extensor strength measures in combat sports athletes: the role of movement velocity and limb side

Background

Maximal isokinetic strength ratios of joint flexors and extensors are important parameters to indicate the level of muscular balance at the joint. Further, in combat sports athletes, upper and lower limb muscle strength is affected by the type of sport. Thus, this study aimed to examine the differences in maximal isokinetic strength of the flexors and extensors and the corresponding flexor–extensor strength ratios of the elbows and knees in combat sports athletes.

Method

Forty male participants (age = 22.3 ± 2.5 years) from four different combat sports (amateur boxing, taekwondo, karate, and judo; n = 10 per sport) were tested for eccentric peak torque of the elbow/knee flexors (EF/KF) and concentric peak torque of the elbow/knee extensors (EE/KE) at three different angular velocities (60, 120, and 180°/s) on the dominant and non-dominant side using an isokinetic device.

Results

Analyses revealed significant, large-sized group × velocity × limb interactions for EF, EE, and EF–EE ratio, KF, KE, and KF–KE ratio (p ≤ 0.03; 0.91 ≤ d ≤ 1.75). Post-hoc analyses indicated that amateur boxers displayed the largest EE strength values on the non-dominant side at ≤ 120°/s and the dominant side at ≥ 120°/s (p < 0.03; 1.21 ≤ d ≤ 1.59). The largest EF–EE strength ratios were observed on amateur boxers’ and judokas’ non-dominant side at ≥ 120°/s (p < 0.04; 1.36 ≤ d ≤ 2.44). Further, we found lower KF–KE strength measures in karate (p < 0.04; 1.12 ≤ d ≤ 6.22) and judo athletes (p ≤ 0.03; 1.60 ≤ d ≤ 5.31) particularly on the non-dominant side.

Conclusions

The present findings indicated combat sport-specific differences in maximal isokinetic strength measures of EF, EE, KF, and KE particularly in favor of amateur boxers on the non-dominant side.

Trial registration: This study does not report results related to health care interventions using human participants and therefore it was not prospectively registered.

The effects of eccentric hamstring exercise training in young female handball players

Purpose

The multidimensional role of hamstring muscle group strength in athletic performance and injury prevention is well documented, and nordic hamstring exercise (NHE) is a popular method for the development of hamstring strength. Our aim was to examine the EMG characteristics of the eccentric NHE as well as the effects of long-term eccentric NHE training on muscle strength and vertical jump performance in 10- to 11-year-old female handball players.

Methods

Players from the same handball team were randomly assigned to an eccentric NHE training (13 players) or a control group (10 players). Both groups continued their regular handball training routine, but the NHE group performed additional eccentric NHE exercises once or twice a week, with progressively increasing volume, over 20 weeks. To test training effects, countermovement jump (CMJ) height, eccentric hamstring impulse, peak torque, and angle of peak torque were evaluated before, during and after the training period. In the pre-exercise test, EMG activity of the medial and lateral hamstring muscle was also assessed during NHE.

Results

Hamstring activities ranged between 98 and 129%. Lateral hamstring activity was greater than medial only in the right leg during NHE. Eccentric hamstring impulse improved in both legs at 10 weeks in both groups. Then, at 20 weeks, it remained unchanged in the NHE but decreased in controls. A similar adaptation was seen in eccentric hamstring torque, without change in the optimum knee angle. CMJ height improved only in the NHE.

Conclusion

It is concluded that NHE activates the hamstring musculature effectively, and a favourable mechanical adaptation to long-term NHE exercise in girls can be triggered as early as 11 years of age.

Effects of a Self-Regulated Training Program on the Repeated Power in Female College Handball Players: An Intervention Study

Several resistance training programs using conventional methodologies have been implemented with the purpose of improving the ability to perform power actions in handball, especially during the competitive season. In contrast, methodologies based on a contemporary perspective, which considers the human being as a self-regulating biological entity, and designed specifically for female college players, are scarce. The aim of this research was to investigate the effects of an eight-week resistance training program, in which the athletes were able to control the loads according to their self-perceived effort and rest on their repeated shuttle sprint and jump ability. The sample was composed of 16 female players of a handball team from the faculty of physics and mathematics sciences of a Chilean university. The RSSJA test was used to evaluate players' conditions pre- and post-training program, and the self-perceived effort scale called OMNI-RES was used for the prediction and control of loads. Results indicated that, after the application of an eight-week resistance training program, significant improvements p ≤ 0.05 on the jump height (pre: 1836.4 W; average post: 2088.9 W) and running speed (average pre: 3.2 m/s; average post: 4.0 m/s) were obtained, as well as a significant reduction in the loss of power and speed between each set of the applied test.

Eccentric Resistance Training in Youth: A Survey of Perceptions and Current Practices by Strength and Conditioning Coaches

BACKGROUND

Eccentric resistance training (ERT) in youth is advocated for aiding performance and injury risk. However, research investigating the applied practices of ERT in youth is in its infancy. In this study, we surveyed the perceptions and practices of practitioners utilizing ERT in youth to provide an understanding of its current application in practice.

METHODS

Sixty-four strength and conditioning coaches completed an online survey reporting their current use of ERT in youth using both open and closed questions.

RESULTS

Coaches deemed the inclusion of ERT important in youth with its inclusion based upon factors such as maturation status, training age and strength levels. Coaches also displayed an awareness of the physiological responses to eccentric exercise in youth compared to adults. ERT was primarily used for injury prevention, with the majority of coaches using body-weight and tempo exercises. Furthermore, utilizing eccentric hamstrings exercises was reported as highly important. The frequency of ERT tended to increase in older age groups and coaches mainly prescribed self-selected rest intervals. Finally, the need for further research into the training guidelines of ERT in youth was highlighted, in which coaches require more information on how maturation influences training adaptations and the fatigue-recovery responses.

CONCLUSION

Coaches emphasized the importance of including ERT for both performance and injury prevention factors in youth although further research is required to generate practical guidelines for coaches in order to support its inclusion within practice.

Eccentric Resistance Training in Youth: Perspectives for Long-Term Athletic Development

The purpose of this narrative review is to discuss the role of eccentric resistance training in youth and how this training modality can be utilized within long-term physical development. Current literature on responses to eccentric exercise in youth has demonstrated that potential concerns, such as fatigue and muscle damage, compared to adults are not supported. Considering the importance of resistance training for youth athletes and the benefits of eccentric training in enhancing strength, power, speed, and resistance to injury, its inclusion throughout youth may be warranted. In this review we provide a brief overview of the physiological responses to exercise in youth with specific reference to the different responses to eccentric resistance training between children, adolescents, and adults. Thereafter, we discuss the importance of ensuring that force absorption qualities are trained throughout youth and how these may be influenced by growth and maturation. In particular, we propose practical methods on how eccentric resistance training methods can be implemented in youth via the inclusion of efficient landing mechanics, eccentric hamstrings strengthening and flywheel inertia training. This article proposes that the use of eccentric resistance training in youth should be considered a necessity to help develop both physical qualities that underpin sporting performance, as well as reducing injury risk. However, as with any other training modality implemented within youth, careful consideration should be given in accordance with an individual's maturity status, training history and technical competency as well as being underpinned by current long-term physical development guidelines.